Slack take-up device



June 13, 1933. R.F. Dow 1,913,872

SLACK TAKE-UP DEVICE Filed May 4, 1929 2 Sheets-Sheet l fmt@ I AT1-ORNE 5.

June 13, 1933. R. F. Dow 1,913,872

' SLACK TAKE-UP DEVICE Filed May 4. 1929 2 Sheets-Sheet 2 ININTR Patented June 13, 1933 j RICHAR i which I haveshown a. Sue-@ted embodiment I.' DOW, 0F HARTFORD,

a coNNEcrlour, ns'sreivoame` THE WHITNEY MFG. co., 1 or* HARTFORD, ooN-NEo'rIoUT, Av CORPORATION 'orcoNNEoTIoU'r snAoKy TAKE-UP DEVICE i 'Appnea'tin mea M514,

This invention relates ,to a novel and improvedform of slack take-up dev1c'e,'and vvill be best understood from the following description and the annexeddravvings, n;

o the invention and in which;

Fig. 1 is a dia'grammaticl vie'vv of a chain drive having my invention employed there'- With.

Fig. 2 isja face View of the take-up device appearing in Fig. 1.

Fig. 3 is a section on the line' 3-3 of Fig. 2,

' showing the parts in initial position'.

'through the bearing'.

Fig. 4 is a section on'the' lin'e74-4 of Fig.. Fig. 5 isajsection onthe lineV 5-'5'of Fig. 3, looking in the direction of thearrows.

Fig. 6 is a section on the line 6--6 o'fFig. 3.'

Fig..7 Yis avieW correspomling to Fig. 4 but showing the parts in a different position. Fig. V8 is a longitudinal Vsectional vleW Fig.` 9 is a fragmentary longitudinalV Sec'- tionalr view lthrough part of the pivot. for' supporting the bearing, showing 'a modified form of abutment.

Fig; 1o isa Seesen en the use .555 Cif Fig; s, butA looking` in the -opposite direction A-from that'indicated by thea'rrows, and' Withpart's t bearing 6 in acounter-clockvvise direction,

removed. g

Fig'. "11 'is a longitudinal sectional view throughthelpivot, Without the parts usually contained therein. f' l `The invention indspartiCiilar utility in connectionvvith drives for' automobiles, and

.itis to thelikabut-may beusedvvherever it is neces sary to automaticallyY take up the 'slack a' belt or chain. For the salie of simplicity, l vvill llo@ lieder-'stood that by so doing -I do not intend to limit the u seofthe invention to a chain drive, tothe exclusionof aibelt drive. ",Referring'first lto 1, haveshovvn therein1v a v diagrfammatie chain driveA consist- 1, 2 and 3, driven in able sprockets niithe"different shafts.l ,Slack aiandffengaging the length ef chain between these shafts.

hereinafterl 'refery to a chain, although The take-up .device comprises 1929. serial No.A adsso. Y

an idler sprocket 5 which rotates freely upon'r a bearing 6, this bearing being eccentrically mounted on' a pivot 7 upon which it is adapt# ed to rotate. Y. In the form shown, ythe pivot comprises a sleeve, the Vconstruction of Which is best shown in Figs. 3 and 11`and v'vhich has 'its` outer end closed byv a plug8 formingan abut# w ment for a compression spring 9. This maybe held in position by a springvvasher, as indicated in Fig. 3, or 'be threaded into v the sleeve, asl shown in Fig. 9. The otherabutment forthis spring consists of a block 10 connected to a rod 11 disposed in the sleeve. The block 1 0 has oppositely disposedpins 12 extending through longitudinally disposed slots 13 in the sleeve7 and into spiral grooves 14 lin the bearing, whereby longitudinal movement of thebl'ock 10 will cause rotary movement of thebearing. Y DSlidably mounted in the bearing and substantially parallel to its pivot isa pavvl pin 15 urgedtovvards the right of Fig..3, by av spring 16 and having at its righthand end a tooth 1 7.- Thistooth engages with ratchetl 75 teeth 18 formed by a plurality lof recesses ontheface of a flange 19'formed on thesleeve, this engagementpreventing movement of the as viewed in Fig. 1. B' The let-hand end ofthe pin as it appears in Fig. 3, is provided'vvith a knurled surface Wherebyit'may be drawn to the left to disengage the teeth 18, and this'end of the pin is alsoprovided with a transverse lock pin 20normally received in a slot inthe bearing, vvhereby upon Withdrawal ofthe pin 15 towards the-left, it may be turned and thus the locking pin -Will engage'thebearing and prevent further engagementof thetooth 17 With the teeth 18. 1

The sljeevemay 'be secured to the bearing by anyfsuitable meanssuchfa's ajWa-sher 21 engaging the bearing and secured onv the: sleeve by means offav spring-lock washer'22 engaging inalrecess'inzthesleeve.` Any suitable means suc'hfasanut123 and a spring lock Washer 24 may befuse'd for n'uoul'itingv the pivot in a suitahlebearing, itl being understood that 100 the pivot is to be held against rotation by any desired means.

In operation, the pin 15 is first pulled towards the left in F ig. 3 to cause disengagement of the tooth 17 from the teeth 18. Next, the block 10 is forced to the right, as seen in Fig. 3, by any suitable tool, thus compressing the spring 9- and simultaneously causing rotation of the bearing in a counter-clockwise direction to the position shown in Fig. 1. The chain is then threaded over the idler which is mounted on the bearing 6, and the pin 15 returned to operative position. As slack develops in the reach of chain between the shafts 1 and 2, this slack will be automatically ,taken up by rotation of the bearing 6 in-a vclockwise direction, as viewed in Fig...

1, and as indicated by thearrow in that ligure. This rotation is of course caused by expansion of the spring 9.

' f The slack will be taken vup until the pins overcome the resistance of the spring 9 to` such, rotation. The pawl and yratchet arrangement positively prevents backward movement under any circumstances. This arrangement may beomitted, but is preferably used to prevent backward movement and consequent slackening of they chain due to sudden shocks. i

Vhile Iv have shown the invention as embodied in a specific form, it is to be understood that various changes in details may be made without departing from the scope of the invention, and I therefore do'notintend to 'limit myself except by the appended claims.

y I claim y l. A slack take-up device comprising an idler adapted to engage a chain, a. bearing on .which said idler is rotatably mounted, a

sleeve forming a pivot for said bearing and disposed eccentrically to its axis, a block slidably mounted within'the sleeve and having transverse pins received in longitudinal slots Afin' the sleeve and in spiral grooves in thebearing, and a spring urging said block-towards one endof the sleeve. A

' 2. A-slack'take-up device comprising an idler adapted to engage a chain, a bearing on which said idler is rotatably mounted, a

sleeve forming a pivot for said bearing and disposed eccentrically to its axis, a block slid-f ably mounted within the sleeve and having transverse pins received in longitudinal slots in th-e sleeve and inspiral grooves in the bearing, and a spring urging said block towards one end of the sleeve, said end being open, whereby the block may be moved in the other direction by a suitable tool.

3. A slack take-up'device comprising an idler adapted to engage a chain, abearing on which said idler is rotatably mounted, a sleeve forming a pivot for said bearing andV disposed eccentrically to its axis, a block slidably mounted within the sleever and' having transverse pins received in klongitudinal slots in the sleeve and in spiral grooves in the bearing, and aspring urging said block towards one end of the sleeve, the pitch of said grooves Vbeingsuch as to prevent easy movement of the block against the action ofthe spring by rotation of the bearing.

1. A slack take-up device comprising an idler adapted to engage a chain, a bearino` on which said idler is. rotatably mounte a sleeve forming a pivot for said bearing andV disposed eccentrically to its axis, a block slidably mounted within the sleeve and having transverse pins received in longitudinal slots, V1n the sleeve and 1n spiral grooves in the bearing, 'a spring urging said block towards one end ofthe sleeve, a flange on the sleeve in proximity to the bearing and having ratchet teeth facing thel bearing, and a pawl pinslidably mounted `in the bearing and adapted to cooperate with saidteeth, for the o purpose set forth.

5. A slack take-up device comprising' an idler adaptedto engage a chain, abearing on which said idler is rotatably mounted, a sleeve forming a pivot for said bearing and disposed eccentrically to its axis, a block slidably mounted within the sleeve and having a plurality of transversely extending pins spacedv apartaround said block and disposed in longitudmal slots inv thesleeve and in spiral groovesfin thebearing, and a spring urging:

said block towards one end of the sleeve.

6. A slack take-up devicev comprisingan.

idler `adapted to engage a chain, a 'bearing on whichv said idler is rotatablyA mounted, a

sleeve forming a pivot for said'bearing and` disposedeccentrically to itsl axis, a block slidably mounted within the sleeve `and having transverse pins received in longitudinalyslots in the sleeve and in spiralgrooves in the bearing, a spring urging said lock towardsA one end of the'sleeve, a flange on thesleeve in proximity rto thebearing and :having ratchet teeth facing the bearing, a pawl pin slidably mounted inthe bearing and adapted to cooperate with said teeth, and means to hold said pawl pinout of: engagement with said teeth. i v A l 7. A slack take-up device comprising an idler adapted to engage a chain, a bearing on which said idler-is rotatably mounted, a

pivot supporting said bearing and disposed eccentrically to its ax1sa compression springj disposed coaxially withsaidv pivot, a pin ies adapted to be move'd by the action of said spring,` means confiningl the movement of the pin to a path parallel with the axis of the pivot, a spiral groove in said bearing in which said pin is received, Whereb said movement of the pin by said lspring W111 cause rotation of the'bearing in one direction on the pivot,

Y and a pawl and ratchet device preventing rotation of the bearing in the other direction.

RICHARD F. DOW. 

